diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/RelNotes/2.34.0.txt | 109 | ||||
| -rw-r--r-- | Documentation/git-am.txt | 2 | ||||
| -rw-r--r-- | Documentation/git-bugreport.txt | 4 | ||||
| -rw-r--r-- | Documentation/git-bundle.txt | 2 | ||||
| -rw-r--r-- | Documentation/git-config.txt | 3 | ||||
| -rw-r--r-- | Documentation/git-http-backend.txt | 26 | ||||
| -rw-r--r-- | Documentation/git-index-pack.txt | 6 | ||||
| -rw-r--r-- | Documentation/git-maintenance.txt | 57 | ||||
| -rw-r--r-- | Documentation/git-multi-pack-index.txt | 20 | ||||
| -rw-r--r-- | Documentation/git-sparse-checkout.txt | 10 | ||||
| -rw-r--r-- | Documentation/git-upload-pack.txt | 8 | ||||
| -rw-r--r-- | Documentation/git-version.txt | 28 | ||||
| -rw-r--r-- | Documentation/git.txt | 19 | ||||
| -rw-r--r-- | Documentation/technical/api-parse-options.txt | 5 | ||||
| -rw-r--r-- | Documentation/technical/bitmap-format.txt | 71 | ||||
| -rw-r--r-- | Documentation/technical/multi-pack-index.txt | 10 | ||||
| -rw-r--r-- | Documentation/technical/protocol-v2.txt | 8 |
17 files changed, 353 insertions, 35 deletions
diff --git a/Documentation/RelNotes/2.34.0.txt b/Documentation/RelNotes/2.34.0.txt index d21a63ed83..fa8ecedb9e 100644 --- a/Documentation/RelNotes/2.34.0.txt +++ b/Documentation/RelNotes/2.34.0.txt @@ -34,6 +34,28 @@ UI, Workflows & Features interactive when the help.autocorrect configuration variable is set to 'prompt'. + * "git maintenance" scheduler learned to use systemd timers as a + possible backend. + + * "git diff --submodule=diff" showed failure from run_command() when + trying to run diff inside a submodule, when the user manually + removes the submodule directory. + + * "git bundle unbundle" learned to show progress display. + + * In cone mode, the sparse-index code path learned to remove ignored + files (like build artifacts) outside the sparse cone, allowing the + entire directory outside the sparse cone to be removed, which is + especially useful when the sparse patterns change. + + * Taking advantage of the CGI interface, http-backend has been + updated to enable protocol v2 automatically when the other side + asks for it. + + * The credential-cache helper has been adjusted to Windows. + + * The error in "git help no-such-git-command" is handled better. + Performance, Internal Implementation, Development Support etc. @@ -74,6 +96,40 @@ Performance, Internal Implementation, Development Support etc. * Callers from older advice_config[] based API has been updated to use the newer advice_if_enabled() and advice_enabled() API. + * Teach "test_pause" and "debug" helpers to allow using the HOME and + TERM environment variables the user usually uses. + + * "make INSTALL_STRIP=-s install" allows the installation step to use + "install -s" to strip the binaries as they get installed. + + * Code that handles large number of refs in the "git fetch" code + path has been optimized. + + * The reachability bitmap file used to be generated only for a single + pack, but now we've learned to generate bitmaps for history that + span across multiple packfiles. + + * The code to make "git grep" recurse into submodules has been + updated to migrate away from the "add submodule's object store as + an alternate object store" mechanism (which is suboptimal). + + * The tracing of process ancestry information has been enhanced. + + * Reduce number of write(2) system calls while sending the + ref advertisement. + + * Update the build procedure to use the "-pedantic" build when + DEVELOPER makefile macro is in effect. + + * Large part of "git submodule add" gets rewritten in C. + + * The run-command API has been updated so that the callers can easily + ask the file descriptors open for packfiles to be closed immediately + before spawning commands that may trigger auto-gc. + + * An oddball OPTION_ARGUMENT feature has been removed from the + parse-options API. + Fixes since v2.33 ----------------- @@ -168,6 +224,49 @@ Fixes since v2.33 * Doc update plus improved error reporting. (merge 1e93770888 jk/log-warn-on-bogus-encoding later to maint). + * Recent "diff -m" changes broke "gitk", which has been corrected. + (merge 5acffd3473 so/diff-index-regression-fix later to maint). + + * Regression fix. + (merge b996f84989 ab/send-email-config-fix later to maint). + + * The "git apply -3" code path learned not to bother the lower level + merge machinery when the three-way merge can be trivially resolved + without the content level merge. This fixes a regression caused by + recent "-3way first and fall back to direct application" change. + (merge 57f183b698 jc/trivial-threeway-binary-merge later to maint). + + * The code that optionally creates the *.rev reverse index file has + been optimized to avoid needless computation when it is not writing + the file out. + (merge 8fe8bae9d2 ab/reverse-midx-optim later to maint). + + * "git range-diff -I... <range> <range>" segfaulted, which has been + corrected. + (merge 709b3f32d3 rs/range-diff-avoid-segfault-with-I later to maint). + + * The order in which various files that make up a single (conceptual) + packfile has been reevaluated and straightened up. This matters in + correctness, as an incomplete set of files must not be shown to a + running Git. + (merge 4bc1fd6e39 tb/pack-finalize-ordering later to maint). + + * The "mode" word is useless in a call to open(2) that does not + create a new file. Such a call in the files backend of the ref + subsystem has been cleaned up. + (merge 35cf94eaf6 rs/no-mode-to-open-when-appending later to maint). + + * "git update-ref --stdin" failed to flush its output as needed, + which potentially led the conversation to a deadlock. + (merge 7c1200745b ps/update-ref-batch-flush later to maint). + + * When "git am --abort" fails to abort correctly, it still exited + with exit status of 0, which has been corrected. + (merge c5ead19ea2 en/am-abort-fix later to maint). + + * Correct nr and alloc members of strvec struct to be of type size_t. + (merge 8d133a4653 jk/strvec-typefix later to maint). + * Other code cleanup, docfix, build fix, etc. (merge 1d9c8daef8 ab/bundle-doc later to maint). (merge 81483fe613 en/merge-strategy-docs later to maint). @@ -194,3 +293,13 @@ Fixes since v2.33 (merge e4f8d27585 rs/show-branch-simplify later to maint). (merge e124ecf7f7 rs/archive-use-object-id later to maint). (merge cebead1ebf cb/ci-build-pedantic later to maint). + (merge ca0cc98e03 bs/doc-bugreport-outdir later to maint). + (merge 72b113e562 ab/no-more-check-bindir later to maint). + (merge 92a5d1c9b4 jc/prefix-filename-allocates later to maint). + (merge d9a65b6c0a rs/setup-use-xopen-and-xdup later to maint). + (merge e8f55568de jk/t5562-racefix later to maint). + (merge 8f0f110156 rs/drop-core-compression-vars later to maint). + (merge b6d8887d3d ma/doc-git-version later to maint). + (merge 66c0c44df6 cb/plug-leaks-in-alloca-emu-users later to maint). + (merge afb32e8101 kz/revindex-comment-fix later to maint). + (merge ae578de926 po/git-config-doc-mentions-help-c later to maint). diff --git a/Documentation/git-am.txt b/Documentation/git-am.txt index 8714dfcb76..0a4a984dfd 100644 --- a/Documentation/git-am.txt +++ b/Documentation/git-am.txt @@ -178,6 +178,8 @@ default. You can use `--no-utf8` to override this. --abort:: Restore the original branch and abort the patching operation. + Revert contents of files involved in the am operation to their + pre-am state. --quit:: Abort the patching operation but keep HEAD and the index diff --git a/Documentation/git-bugreport.txt b/Documentation/git-bugreport.txt index 66e88c2e31..d8817bf3ce 100644 --- a/Documentation/git-bugreport.txt +++ b/Documentation/git-bugreport.txt @@ -40,8 +40,8 @@ OPTIONS ------- -o <path>:: --output-directory <path>:: - Place the resulting bug report file in `<path>` instead of the root of - the Git repository. + Place the resulting bug report file in `<path>` instead of the current + directory. -s <format>:: --suffix <format>:: diff --git a/Documentation/git-bundle.txt b/Documentation/git-bundle.txt index ac0d003835..71b5ecabd1 100644 --- a/Documentation/git-bundle.txt +++ b/Documentation/git-bundle.txt @@ -13,7 +13,7 @@ SYNOPSIS [--version=<version>] <file> <git-rev-list-args> 'git bundle' verify [-q | --quiet] <file> 'git bundle' list-heads <file> [<refname>...] -'git bundle' unbundle <file> [<refname>...] +'git bundle' unbundle [--progress] <file> [<refname>...] DESCRIPTION ----------- diff --git a/Documentation/git-config.txt b/Documentation/git-config.txt index 2dc4bae6da..992225f612 100644 --- a/Documentation/git-config.txt +++ b/Documentation/git-config.txt @@ -71,6 +71,9 @@ codes are: On success, the command returns the exit code 0. +A list of all available configuration variables can be obtained using the +`git help --config` command. + [[OPTIONS]] OPTIONS ------- diff --git a/Documentation/git-http-backend.txt b/Documentation/git-http-backend.txt index 558966aa83..0c5c0dde19 100644 --- a/Documentation/git-http-backend.txt +++ b/Documentation/git-http-backend.txt @@ -16,7 +16,9 @@ A simple CGI program to serve the contents of a Git repository to Git clients accessing the repository over http:// and https:// protocols. The program supports clients fetching using both the smart HTTP protocol and the backwards-compatible dumb HTTP protocol, as well as clients -pushing using the smart HTTP protocol. +pushing using the smart HTTP protocol. It also supports Git's +more-efficient "v2" protocol if properly configured; see the +discussion of `GIT_PROTOCOL` in the ENVIRONMENT section below. It verifies that the directory has the magic file "git-daemon-export-ok", and it will refuse to export any Git directory @@ -77,6 +79,18 @@ Apache 2.x:: SetEnv GIT_PROJECT_ROOT /var/www/git SetEnv GIT_HTTP_EXPORT_ALL ScriptAlias /git/ /usr/libexec/git-core/git-http-backend/ + +# This is not strictly necessary using Apache and a modern version of +# git-http-backend, as the webserver will pass along the header in the +# environment as HTTP_GIT_PROTOCOL, and http-backend will copy that into +# GIT_PROTOCOL. But you may need this line (or something similar if you +# are using a different webserver), or if you want to support older Git +# versions that did not do that copying. +# +# Having the webserver set up GIT_PROTOCOL is perfectly fine even with +# modern versions (and will take precedence over HTTP_GIT_PROTOCOL, +# which means it can be used to override the client's request). +SetEnvIf Git-Protocol ".*" GIT_PROTOCOL=$0 ---------------------------------------------------------------- + To enable anonymous read access but authenticated write access, @@ -264,6 +278,16 @@ a repository with an extremely large number of refs. The value can be specified with a unit (e.g., `100M` for 100 megabytes). The default is 10 megabytes. +Clients may probe for optional protocol capabilities (like the v2 +protocol) using the `Git-Protocol` HTTP header. In order to support +these, the contents of that header must appear in the `GIT_PROTOCOL` +environment variable. Most webservers will pass this header to the CGI +via the `HTTP_GIT_PROTOCOL` variable, and `git-http-backend` will +automatically copy that to `GIT_PROTOCOL`. However, some webservers may +be more selective about which headers they'll pass, in which case they +need to be configured explicitly (see the mention of `Git-Protocol` in +the Apache config from the earlier EXAMPLES section). + The backend process sets GIT_COMMITTER_NAME to '$REMOTE_USER' and GIT_COMMITTER_EMAIL to '$\{REMOTE_USER}@http.$\{REMOTE_ADDR\}', ensuring that any reflogs created by 'git-receive-pack' contain some diff --git a/Documentation/git-index-pack.txt b/Documentation/git-index-pack.txt index 7fa74b9e79..1f1e359225 100644 --- a/Documentation/git-index-pack.txt +++ b/Documentation/git-index-pack.txt @@ -82,6 +82,12 @@ OPTIONS --strict:: Die, if the pack contains broken objects or links. +--progress-title:: + For internal use only. ++ +Set the title of the progress bar. The title is "Receiving objects" by +default and "Indexing objects" when `--stdin` is specified. + --check-self-contained-and-connected:: Die if the pack contains broken links. For internal use only. diff --git a/Documentation/git-maintenance.txt b/Documentation/git-maintenance.txt index 1e738ad398..e2cfb68ab5 100644 --- a/Documentation/git-maintenance.txt +++ b/Documentation/git-maintenance.txt @@ -179,6 +179,17 @@ OPTIONS `maintenance.<task>.enabled` configured as `true` are considered. See the 'TASKS' section for the list of accepted `<task>` values. +--scheduler=auto|crontab|systemd-timer|launchctl|schtasks:: + When combined with the `start` subcommand, specify the scheduler + for running the hourly, daily and weekly executions of + `git maintenance run`. + Possible values for `<scheduler>` are `auto`, `crontab` + (POSIX), `systemd-timer` (Linux), `launchctl` (macOS), and + `schtasks` (Windows). When `auto` is specified, the + appropriate platform-specific scheduler is used; on Linux, + `systemd-timer` is used if available, otherwise + `crontab`. Default is `auto`. + TROUBLESHOOTING --------------- @@ -277,6 +288,52 @@ schedule to ensure you are executing the correct binaries in your schedule. +BACKGROUND MAINTENANCE ON LINUX SYSTEMD SYSTEMS +----------------------------------------------- + +While Linux supports `cron`, depending on the distribution, `cron` may +be an optional package not necessarily installed. On modern Linux +distributions, systemd timers are superseding it. + +If user systemd timers are available, they will be used as a replacement +of `cron`. + +In this case, `git maintenance start` will create user systemd timer units +and start the timers. The current list of user-scheduled tasks can be found +by running `systemctl --user list-timers`. The timers written by `git +maintenance start` are similar to this: + +----------------------------------------------------------------------- +$ systemctl --user list-timers +NEXT LEFT LAST PASSED UNIT ACTIVATES +Thu 2021-04-29 19:00:00 CEST 42min left Thu 2021-04-29 18:00:11 CEST 17min ago git-maintenance@hourly.timer git-maintenance@hourly.service +Fri 2021-04-30 00:00:00 CEST 5h 42min left Thu 2021-04-29 00:00:11 CEST 18h ago git-maintenance@daily.timer git-maintenance@daily.service +Mon 2021-05-03 00:00:00 CEST 3 days left Mon 2021-04-26 00:00:11 CEST 3 days ago git-maintenance@weekly.timer git-maintenance@weekly.service +----------------------------------------------------------------------- + +One timer is registered for each `--schedule=<frequency>` option. + +The definition of the systemd units can be inspected in the following files: + +----------------------------------------------------------------------- +~/.config/systemd/user/git-maintenance@.timer +~/.config/systemd/user/git-maintenance@.service +~/.config/systemd/user/timers.target.wants/git-maintenance@hourly.timer +~/.config/systemd/user/timers.target.wants/git-maintenance@daily.timer +~/.config/systemd/user/timers.target.wants/git-maintenance@weekly.timer +----------------------------------------------------------------------- + +`git maintenance start` will overwrite these files and start the timer +again with `systemctl --user`, so any customization should be done by +creating a drop-in file, i.e. a `.conf` suffixed file in the +`~/.config/systemd/user/git-maintenance@.service.d` directory. + +`git maintenance stop` will stop the user systemd timers and delete +the above mentioned files. + +For more details, see `systemd.timer(5)`. + + BACKGROUND MAINTENANCE ON MACOS SYSTEMS --------------------------------------- diff --git a/Documentation/git-multi-pack-index.txt b/Documentation/git-multi-pack-index.txt index ffd601bc17..a9df3dbd32 100644 --- a/Documentation/git-multi-pack-index.txt +++ b/Documentation/git-multi-pack-index.txt @@ -10,7 +10,7 @@ SYNOPSIS -------- [verse] 'git multi-pack-index' [--object-dir=<dir>] [--[no-]progress] - [--preferred-pack=<pack>] <subcommand> + [--preferred-pack=<pack>] [--[no-]bitmap] <subcommand> DESCRIPTION ----------- @@ -23,6 +23,8 @@ OPTIONS Use given directory for the location of Git objects. We check `<dir>/packs/multi-pack-index` for the current MIDX file, and `<dir>/packs` for the pack-files to index. ++ +`<dir>` must be an alternate of the current repository. --[no-]progress:: Turn progress on/off explicitly. If neither is specified, progress is @@ -37,9 +39,12 @@ write:: -- --preferred-pack=<pack>:: Optionally specify the tie-breaking pack used when - multiple packs contain the same object. If not given, - ties are broken in favor of the pack with the lowest - mtime. + multiple packs contain the same object. `<pack>` must + contain at least one object. If not given, ties are + broken in favor of the pack with the lowest mtime. + + --[no-]bitmap:: + Control whether or not a multi-pack bitmap is written. -- verify:: @@ -81,6 +86,13 @@ EXAMPLES $ git multi-pack-index write ----------------------------------------------- +* Write a MIDX file for the packfiles in the current .git folder with a +corresponding bitmap. ++ +------------------------------------------------------------- +$ git multi-pack-index write --preferred-pack=<pack> --bitmap +------------------------------------------------------------- + * Write a MIDX file for the packfiles in an alternate object store. + ----------------------------------------------- diff --git a/Documentation/git-sparse-checkout.txt b/Documentation/git-sparse-checkout.txt index fdcf43f87c..42056ee9ff 100644 --- a/Documentation/git-sparse-checkout.txt +++ b/Documentation/git-sparse-checkout.txt @@ -210,6 +210,16 @@ case-insensitive check. This corrects for case mismatched filenames in the 'git sparse-checkout set' command to reflect the expected cone in the working directory. +When changing the sparse-checkout patterns in cone mode, Git will inspect each +tracked directory that is not within the sparse-checkout cone to see if it +contains any untracked files. If all of those files are ignored due to the +`.gitignore` patterns, then the directory will be deleted. If any of the +untracked files within that directory is not ignored, then no deletions will +occur within that directory and a warning message will appear. If these files +are important, then reset your sparse-checkout definition so they are included, +use `git add` and `git commit` to store them, then remove any remaining files +manually to ensure Git can behave optimally. + SUBMODULES ---------- diff --git a/Documentation/git-upload-pack.txt b/Documentation/git-upload-pack.txt index 739416ec83..8f87b23ea8 100644 --- a/Documentation/git-upload-pack.txt +++ b/Documentation/git-upload-pack.txt @@ -48,6 +48,14 @@ OPTIONS <directory>:: The repository to sync from. +ENVIRONMENT +----------- + +`GIT_PROTOCOL`:: + Internal variable used for handshaking the wire protocol. Server + admins may need to configure some transports to allow this + variable to be passed. See the discussion in linkgit:git[1]. + SEE ALSO -------- linkgit:gitnamespaces[7] diff --git a/Documentation/git-version.txt b/Documentation/git-version.txt new file mode 100644 index 0000000000..80fa7754a6 --- /dev/null +++ b/Documentation/git-version.txt @@ -0,0 +1,28 @@ +git-version(1) +============== + +NAME +---- +git-version - Display version information about Git + +SYNOPSIS +-------- +[verse] +'git version' [--build-options] + +DESCRIPTION +----------- +With no options given, the version of 'git' is printed on the standard output. + +Note that `git --version` is identical to `git version` because the +former is internally converted into the latter. + +OPTIONS +------- +--build-options:: + Include additional information about how git was built for diagnostic + purposes. + +GIT +--- +Part of the linkgit:git[1] suite diff --git a/Documentation/git.txt b/Documentation/git.txt index 6dd241ef83..abace9eac2 100644 --- a/Documentation/git.txt +++ b/Documentation/git.txt @@ -41,6 +41,10 @@ OPTIONS ------- --version:: Prints the Git suite version that the 'git' program came from. ++ +This option is internaly converted to `git version ...` and accepts +the same options as the linkgit:git-version[1] command. If `--help` is +also given, it takes precedence over `--version`. --help:: Prints the synopsis and a list of the most commonly used @@ -894,6 +898,21 @@ for full details. Contains a colon ':' separated list of keys with optional values 'key[=value]'. Presence of unknown keys and values must be ignored. ++ +Note that servers may need to be configured to allow this variable to +pass over some transports. It will be propagated automatically when +accessing local repositories (i.e., `file://` or a filesystem path), as +well as over the `git://` protocol. For git-over-http, it should work +automatically in most configurations, but see the discussion in +linkgit:git-http-backend[1]. For git-over-ssh, the ssh server may need +to be configured to allow clients to pass this variable (e.g., by using +`AcceptEnv GIT_PROTOCOL` with OpenSSH). ++ +This configuration is optional. If the variable is not propagated, then +clients will fall back to the original "v0" protocol (but may miss out +on some performance improvements or features). This variable currently +only affects clones and fetches; it is not yet used for pushes (but may +be in the future). `GIT_OPTIONAL_LOCKS`:: If set to `0`, Git will complete any requested operation without diff --git a/Documentation/technical/api-parse-options.txt b/Documentation/technical/api-parse-options.txt index 5a60bbfa7f..acfd5dc1d8 100644 --- a/Documentation/technical/api-parse-options.txt +++ b/Documentation/technical/api-parse-options.txt @@ -198,11 +198,6 @@ There are some macros to easily define options: The filename will be prefixed by passing the filename along with the prefix argument of `parse_options()` to `prefix_filename()`. -`OPT_ARGUMENT(long, &int_var, description)`:: - Introduce a long-option argument that will be kept in `argv[]`. - If this option was seen, `int_var` will be set to one (except - if a `NULL` pointer was passed). - `OPT_NUMBER_CALLBACK(&var, description, func_ptr)`:: Recognize numerical options like -123 and feed the integer as if it was an argument to the function given by `func_ptr`. diff --git a/Documentation/technical/bitmap-format.txt b/Documentation/technical/bitmap-format.txt index f8c18a0f7a..04b3ec2178 100644 --- a/Documentation/technical/bitmap-format.txt +++ b/Documentation/technical/bitmap-format.txt @@ -1,6 +1,44 @@ GIT bitmap v1 format ==================== +== Pack and multi-pack bitmaps + +Bitmaps store reachability information about the set of objects in a packfile, +or a multi-pack index (MIDX). The former is defined obviously, and the latter is +defined as the union of objects in packs contained in the MIDX. + +A bitmap may belong to either one pack, or the repository's multi-pack index (if +it exists). A repository may have at most one bitmap. + +An object is uniquely described by its bit position within a bitmap: + + - If the bitmap belongs to a packfile, the __n__th bit corresponds to + the __n__th object in pack order. For a function `offset` which maps + objects to their byte offset within a pack, pack order is defined as + follows: + + o1 <= o2 <==> offset(o1) <= offset(o2) + + - If the bitmap belongs to a MIDX, the __n__th bit corresponds to the + __n__th object in MIDX order. With an additional function `pack` which + maps objects to the pack they were selected from by the MIDX, MIDX order + is defined as follows: + + o1 <= o2 <==> pack(o1) <= pack(o2) /\ offset(o1) <= offset(o2) + + The ordering between packs is done according to the MIDX's .rev file. + Notably, the preferred pack sorts ahead of all other packs. + +The on-disk representation (described below) of a bitmap is the same regardless +of whether or not that bitmap belongs to a packfile or a MIDX. The only +difference is the interpretation of the bits, which is described above. + +Certain bitmap extensions are supported (see: Appendix B). No extensions are +required for bitmaps corresponding to packfiles. For bitmaps that correspond to +MIDXs, both the bit-cache and rev-cache extensions are required. + +== On-disk format + - A header appears at the beginning: 4-byte signature: {'B', 'I', 'T', 'M'} @@ -14,17 +52,19 @@ GIT bitmap v1 format The following flags are supported: - BITMAP_OPT_FULL_DAG (0x1) REQUIRED - This flag must always be present. It implies that the bitmap - index has been generated for a packfile with full closure - (i.e. where every single object in the packfile can find - its parent links inside the same packfile). This is a - requirement for the bitmap index format, also present in JGit, - that greatly reduces the complexity of the implementation. + This flag must always be present. It implies that the + bitmap index has been generated for a packfile or + multi-pack index (MIDX) with full closure (i.e. where + every single object in the packfile/MIDX can find its + parent links inside the same packfile/MIDX). This is a + requirement for the bitmap index format, also present in + JGit, that greatly reduces the complexity of the + implementation. - BITMAP_OPT_HASH_CACHE (0x4) If present, the end of the bitmap file contains `N` 32-bit name-hash values, one per object in the - pack. The format and meaning of the name-hash is + pack/MIDX. The format and meaning of the name-hash is described below. 4-byte entry count (network byte order) @@ -33,7 +73,8 @@ GIT bitmap v1 format 20-byte checksum - The SHA1 checksum of the pack this bitmap index belongs to. + The SHA1 checksum of the pack/MIDX this bitmap index + belongs to. - 4 EWAH bitmaps that act as type indexes @@ -50,7 +91,7 @@ GIT bitmap v1 format - Tags In each bitmap, the `n`th bit is set to true if the `n`th object - in the packfile is of that type. + in the packfile or multi-pack index is of that type. The obvious consequence is that the OR of all 4 bitmaps will result in a full set (all bits set), and the AND of all 4 bitmaps will @@ -62,8 +103,9 @@ GIT bitmap v1 format Each entry contains the following: - 4-byte object position (network byte order) - The position **in the index for the packfile** where the - bitmap for this commit is found. + The position **in the index for the packfile or + multi-pack index** where the bitmap for this commit is + found. - 1-byte XOR-offset The xor offset used to compress this bitmap. For an entry @@ -146,10 +188,11 @@ Name-hash cache --------------- If the BITMAP_OPT_HASH_CACHE flag is set, the end of the bitmap contains -a cache of 32-bit values, one per object in the pack. The value at +a cache of 32-bit values, one per object in the pack/MIDX. The value at position `i` is the hash of the pathname at which the `i`th object -(counting in index order) in the pack can be found. This can be fed -into the delta heuristics to compare objects with similar pathnames. +(counting in index or multi-pack index order) in the pack/MIDX can be found. +This can be fed into the delta heuristics to compare objects with similar +pathnames. The hash algorithm used is: diff --git a/Documentation/technical/multi-pack-index.txt b/Documentation/technical/multi-pack-index.txt index fb688976c4..1a73c3ee20 100644 --- a/Documentation/technical/multi-pack-index.txt +++ b/Documentation/technical/multi-pack-index.txt @@ -71,14 +71,10 @@ Future Work still reducing the number of binary searches required for object lookups. -- The reachability bitmap is currently paired directly with a single - packfile, using the pack-order as the object order to hopefully - compress the bitmaps well using run-length encoding. This could be - extended to pair a reachability bitmap with a multi-pack-index. If - the multi-pack-index is extended to store a "stable object order" +- If the multi-pack-index is extended to store a "stable object order" (a function Order(hash) = integer that is constant for a given hash, - even as the multi-pack-index is updated) then a reachability bitmap - could point to a multi-pack-index and be updated independently. + even as the multi-pack-index is updated) then MIDX bitmaps could be + updated independently of the MIDX. - Packfiles can be marked as "special" using empty files that share the initial name but replace ".pack" with ".keep" or ".promisor". diff --git a/Documentation/technical/protocol-v2.txt b/Documentation/technical/protocol-v2.txt index 9347b2ad13..21e8258ccf 100644 --- a/Documentation/technical/protocol-v2.txt +++ b/Documentation/technical/protocol-v2.txt @@ -42,7 +42,8 @@ Initial Client Request In general a client can request to speak protocol v2 by sending `version=2` through the respective side-channel for the transport being used which inevitably sets `GIT_PROTOCOL`. More information can be -found in `pack-protocol.txt` and `http-protocol.txt`. In all cases the +found in `pack-protocol.txt` and `http-protocol.txt`, as well as the +`GIT_PROTOCOL` definition in `git.txt`. In all cases the response from the server is the capability advertisement. Git Transport @@ -58,6 +59,8 @@ SSH and File Transport When using either the ssh:// or file:// transport, the GIT_PROTOCOL environment variable must be set explicitly to include "version=2". +The server may need to be configured to allow this environment variable +to pass. HTTP Transport ~~~~~~~~~~~~~~ @@ -84,6 +87,9 @@ Subsequent requests are then made directly to the service Uses the `--http-backend-info-refs` option to linkgit:git-upload-pack[1]. +The server may need to be configured to pass this header's contents via +the `GIT_PROTOCOL` variable. See the discussion in `git-http-backend.txt`. + Capability Advertisement ------------------------ |